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861.
862.
INTRODUCTION: Elderly patients who suffer trauma have a higher mortality and use disproportionately more trauma resources than younger patients. To compare these 2 groups and determine the outcomes and characteristics of elderly patients, we reviewed patients in these 2 groups admitted and treated in our tertiary care provincial trauma centre. METHODS: From the provincial trauma registry we selected a cohort of 40 geriatric patients (group 1) (> or = 65 yr of age) with an ISS of 16 or more who were admitted to and spent time in our trauma service for more than 48 hours and compared them with a similar randomly selected cohort of 44 patients (group 2) aged 20-30 years. Family physicians were contacted for follow-up of these patients 2 years after discharge. We considered length of hospital stay, complications, disposition of the patients and use of consultation services. RESULTS: Patients in group 1 had a mean age of 72.1 years (range from 65-98 yr) and a mean ISS of 27.3 (range from 17-50). Patients in group 2 had a mean age of 26.3 years (range from 22-29 yr) and a mean ISS of 26.3 (range from 17-54). Hospital stay was significantly longer in the group 1: 34.5 days (95% confidence interval [CI]: 24-44 d) versus 21.6 days (95% CI: 15-28 d). More elderly patients experienced complications (35 v. 13, p < 0.001) and required medical consultations (35 v. 26, p < 0.001). In-hospital death rates were 8% (3 of 40) and 4% (2 of 44) respectively (p = 0.3). Fewer geriatric patients could be discharged home (35% [14 of 40] v. 27% [22 of 44], p = 0.056) or to rehabilitation facilities (28% [11 of 40] v. 34% [15 of 44], p = 0.3). Five geriatric patients were discharged to nursing homes (p = 0.007). Of the geriatric patients discharged to rehabilitation facilities or home, 75% were independent 2 years after discharge. CONCLUSIONS: Aggressive care for geriatric trauma patients is warranted, and resources should be directed toward rehabilitation. Based on our findings, we expect that creating a directed care pathway for these patients, targetting complications and earlier discharge, will further improve their outcomes.  相似文献   
863.
OBJECTIVE: To report a retrospective review of patients with a testicular germ cell tumour treated in a large cancer centre who developed a second tumour, as 1.8-5% of such patients will subsequently develop a new primary tumour in the contralateral testis. PATIENTS AND METHODS: From a database of 570 men treated for testicular cancer in the West of Scotland between 1989 and 1998, all those who developed bilateral testicular tumours were identified. RESULTS: Nineteen men (3.3%) developed a second primary testicular malignancy; the mean age at diagnosis of the first tumour was 29.5 years, with the mean (range) interval to diagnosis of the second tumour of 76 (11-181) months (except for one man with synchronous tumours). The first tumour was teratoma in 11 and seminoma in seven; one patient had synchronous bilateral teratoma. The second primary was teratoma in 10 and seminoma in eight. Known risk factors for carcinoma in situ were present in nine patients, i.e. a small atrophic contralateral testis in five, a family history of testicular cancer in two, a history of infertility in two and unilateral undescended testis in one. Two patients had had contralateral testicular biopsies at the first diagnosis; both were negative for intratubular germ cell neoplasia (IGCN). Eight patients had chemotherapy to treat the first tumour and 14 for the second. All underwent bilateral orchidectomy. Overall, 18 of 19 men are alive and disease-free, with a median follow-up of 51 months. Pathology for 12 of the second testicular tumours was available for review; there was no IGCN in any of the slides from three patients, it was only present focally around the tumour in seven, and was diffuse in two patients. CONCLUSIONS: Chemotherapy for the first testicular tumour does not eliminate the risk of developing a contralateral tumour. Despite careful follow-up, in most patients the second primary tumour was not diagnosed early enough to avoid chemotherapy. The focal nature of IGCN in the second testis in most patients questions the value of biopsy of the contralateral testis. Improved methods of detecting patients at risk of second testicular tumours are needed.  相似文献   
864.
We experienced two cases with anomalous origin of the left anterior descending artery (LAD) from the proximal right coronary artery requiring coronary artery bypass grafting. A 66-yr old female with a long history of angina and a positive stress test had the anomalous artery coursing anterior to the right ventricular outflow tract. A 42-yr old male with worsening angina after an anteroseptal myocardial infarction had the anomalous artery running between the great vessels. Both patients underwent left internal mammary artery-to-LAD bypass on the beating heart with complete resolution of ischemic symptoms.Isolated coronary artery anomaly is an uncommon disease (0.6-1.2%) in patients undergoing cardiac catheterization. An anomalous origin of the LAD from the proximal right coronary artery (RCA) or the right sinus of Valsalva (RSV) is very rare, found in 1.2-6.1% of all coronary anomalies. This coronary anomaly has been considered potentially serious but functionally unimportant. We report two cases of anomalous LAD from the proximal RCA resulting in anterior wall ischemia which was effectively treated by coronary artery bypass surgery.  相似文献   
865.
Development of a reconstructed human skin model for angiogenesis   总被引:4,自引:0,他引:4  
We have previously shown that reconstructed human skin engineered from autologous keratinocytes, fibroblasts, and sterilized donor allodermis stimulates angiogenesis within 5-7 days when placed on well-vascularized wound beds in nude mice. When this reconstructed skin was used clinically in more demanding wound beds, some grafts were lost, possibly due to delayed vascularization. As this reconstructed skin lacks any endothelial cells, our aim in this study was to develop an angiogenic reconstructed skin model in which to explore strategies to improve angiogenesis both in vitro and in vivo. We report that culture of small-vessel human dermal microvascular endothelial cells (HuDMECs) was achieved using magnetic beads coated with an antibody to platelet cell adhesion molecule as a means of purifying the culture. Keratinocytes, fibroblasts, and HuDMECs could be cultured from the same skin biopsy. Initial studies culturing HuDMECs and other sources of endothelial cells with the tissue-engineered skin showed that these cells were capable of slowly entering the dermis under standard culture conditions in vitro. In conclusion, this provides us with a model in which to explore strategies for improving angiogenesis in vitro and also establishes the culture methodologies for the production of reconstructed skin containing autologous keratinocytes, fibroblasts, and endothelial cells.  相似文献   
866.
OBJECTIVE: To determine the enhancement phase providing the highest contrast-to-noise ratio (CNR) between cholangiocarcinoma and liver or portal vein on dynamic and delayed gadolinium-enhanced magnetic resonance imaging (MRI). SUBJECTS AND METHODS: Precontrast, 3-phase dynamic postcontrast, and delayed postcontrast MRI of the liver was performed in 25 patients with cholangiocarcinoma and correlated with surgical findings, pathology, and other imaging studies. Contrast-to-noise ratios for tumor relative to adjacent liver and portal vein were calculated from signal intensities determined from regions of interest obtained for each phase of enhancement. A subjective assessment of the signal intensity of the periportal tissues relative to the portal vein was made for each set of delayed images. RESULTS: A mass was visible in 24 of 25 patients. Tumor masses were hypointense in 92%, 67%, 75%, and 21%; isointense in 8%, 8%, 17%, and 12%; and hyperintense in 0%, 25%, 8%, and 67% of patients relative to liver on precontrast, arterial, portal venous, and delayed images, respectively. No single phase of gadolinium enhancement demonstrated consistently superior tumor-versus-liver CNR. Delayed imaging demonstrated the highest tumor-versus-liver CNR in 25% of patients and the lowest in 33%. The portal venous phase demonstrated the highest tumor-versus-portal vein CNR in 75% of patients. Delayed postcontrast images demonstrated the lowest tumor-versus-portal vein CNR in 38% of patients. Periportal tissues were isointense to portal vein in all but 1 patient on delayed images. CONCLUSION: No single phase of dynamic and delayed gadolinium-enhanced MRI demonstrates superior CNR between cholangiocarcinoma and normally enhancing liver, although the portal phase provides the best CNR between tumor and portal vein in most cases. Although delayed enhancement is typical of cholangiocarcinoma, delayed imaging does not necessarily offer superior contrast between tumor and liver parenchyma compared with other phases of enhancement. Differentiation between tumor and portal vein and periportal tissues may be difficult on delayed images.  相似文献   
867.
This study investigated the reliability and validity of the Visual Gait Assessment Scale when used by experienced and inexperienced observers. Four experienced and six inexperienced observers viewed videotaped footage of four children with hemiplegic cerebral palsy on two separate occasions. Validity of the Scale was obtained by comparison with three-dimensional gait analysis (3DGA). The experienced observers generally had higher inter-observer and intra-observer reliability than the inexperienced observers. Both groups showed higher agreement for assessments made at the ankle and foot than at the knee and hip. The experienced observers had slightly higher agreement with 3DGA than the inexperienced observers. The inexperienced observers showed a learning effect and had higher inter-observer agreement and higher agreement with 3DGA in the second assessment of the videotapes. This scale can be used by inexperienced observers but is limited to observations in the sagittal plane and by poor reliability at the knee and hip for experienced and inexperienced observers.  相似文献   
868.
Magnetic properties characterized by susceptibility and chemical shift linearly modify the local magnetic field experienced by spins. A piece‐wise constant solution using magnetic resonance imaging is found to the challenging inversion problem from field to magnetic properties. The magnetic field shifts were estimated from MR phase images. The MR magnitude images were segmented into many regions of uniform magnetic properties. Standard linear regression using the calculated magnetic field from each region allowed accurate susceptibility quantification. The technique was experimentally validated on a variety of samples including water, vegetable oil, air, Gadolinium, and superparamagnetic iron oxides. Susceptibility was measured with a precision better than 0.1 ppm, in a range of 10 ppm. In vivo feasibility was shown on the forearm for which soft‐tissue, cortical bone, and bone marrow susceptibility, and chemical shift values in good agreement with literature data were obtained. Magn Reson Med 60:1003–1009, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
869.
BACKGROUND: Previous linkage studies have suggested prostate cancer susceptibility genes located on chromosomes 1, 20, and X. Several putative prostate cancer candidate genes have also been identified including RNASEL, MSR1, and ELAC2. Presently, these linkage regions and candidate genes appear to explain only a small proportion of hereditary prostate cancer cases suggesting the need for additional whole genome analyses. METHODS: A genome-wide mode-of-inheritance-free linkage scan, using 405 genetic markers, was conducted on 175 pedigrees, the majority containing three or more affected individuals diagnosed with prostate cancer. Stratified linkage analyses were performed based on previously established criteria. RESULTS: Results based on the entire set of 175 pedigrees showed strong suggestive evidence for linkage on chromosome 17q (LOD = 2.36), with strongest evidence coming from the subset of pedigrees with four or more affected individuals (LOD = 3.27). Race specific analyses revealed strong suggestive evidence for linkage in our African-American pedigrees on chromosome 22q (LOD = 2.35). CONCLUSIONS: Genome-wide analysis of a large set of prostate cancer families indicates new areas of the genome that may harbor prostate cancer susceptibility genes. Specifically, our linkage results suggest that there is a prostate cancer susceptibility gene on chromosome 17 that is independent of ELAC2. Further research including combined analyses of independent genome-wide scan data may clarify the most important regions for future investigation.  相似文献   
870.
OBJECTIVE: The long term survival of patients with mild to moderate aortic valve disease who do not have valve replacement at the time of coronary artery bypass grafting (CABG) is unknown. Therefore we have reviewed our experience with such patients. METHODS: We reviewed the medical records of consecutive patients between June 1978 and December 1996, and identified 40 patients with mild to moderate aortic valve disease, who underwent CABG, without valve replacement (study group). Mean preoperative aortic gradient was 34 mmHg and mean intraoperative gradient 20 mmHg. Eleven patients underwent valve inspection, and an equal number, underwent valve repair. The records of 61 other patients with severe aortic valve disease, who underwent concomitant aortic valve replacement (AVR) and CABG (control group), were also reviewed. RESULTS: Survival was significantly better in the control group. Eleven patients (27.5%) in the study group underwent reoperation for AVR, with no operative mortality. Multivariate analysis confirmed valve replacement at initial CABG to be the only predictor of survival (beta=0.586,P=0.038) Preoperative gradient <40 mmHg, intraoperative gradient <20 mmHg, age over 70, sex, aortic stenosis and valve pathology did not predict survival in the study group. CONCLUSION: Patients with mild to moderate aortic valve disease undergoing coronary artery bypass grafting may be best served by valve replacement, rather than repair, inspection or no procedure.  相似文献   
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